


Root Parasite

by Aryū Muin (Caeslin)



Category: Persona 4
Genre: Body Horror, M/M, Other, Plants, Spoilers, Stomach Bulging, Tentacles, Tentacles in Ears, all the way through
Language: English
Status: Completed
Published: 2016-01-11
Updated: 2016-01-11
Packaged: 2018-05-13 05:15:09
Rating: Explicit
Warnings: Rape/Non-Con, Underage
Chapters: 1
Words: 4,800
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5696383
Author URL: https://archiveofourown.org/users/Caeslin/pseuds/Ary%C5%AB%20Muin
Summary: <blockquote class="userstuff">
              <p>Yosuke gets introduced to a strange plant in the TV world, with some life- (and body-) changing effects.</p>
            </blockquote>





	Root Parasite

**Author's Note:**

> First off, this fic contains spoilers for December! Other than that, it has no meaningful plot.
> 
> Second, this fic contains "all the way through," which is a kink mostly found in hentai tentacle sex scenes that involves something going in one end of a person and out the other, in a non-permanently-body-deforming way. If you want to know more, googling "all the way through hentai" should bring up some NSFW but informative image results.
> 
> Lastly, the content notes:
> 
>  **This story includes (and kinks on)** : non-consensual tentacle sex (with a plant), stomach inflation, tentacles in ears, brainwashing, all the way through, gagging/choking, body horror, and gratuitous physical and emotional abuse of Yosuke for purposes of kink, with Adachi facilitating all of the above. There is no happy end.

_Never go in alone._ It was one of the first rules they'd decided on after they discovered the TV world; a way to make sure they'd all have each other's backs, no matter how dangerous things got.

But Yosuke hadn't been able to wait before going after Adachi. He'd been unable to sleep, tormented by thoughts of Nanako lying in the hospital room, of how close he himself had been to sacrificing Namatame, of how Saki-sempai had been killed at Adachi's hands. He couldn't stand to wait until morning, when Adachi might be gone to who-knows-where; he needed to find Adachi himself, and bring him to justice with his own hands. 

It was nothing to sneak out of his house, to use his employee key to creep into Junes and turn off the security alarms. He'd readied his weapons; turned on a TV; and then he'd jumped in. Simple as that. 

Adachi had been waiting for him. Yosuke had had no chance to fight back before he was taken under.

-

"Rise and shine."

When Yosuke awoke, he was disoriented. He felt groggy and stiff, and his limbs wouldn't move. 

"Thought you'd get the slip on me while I was sleeping, huh? Joke's on you, kid."

He opened his eyes to find Adachi looking down at him. He was wearing a look of bored disinterest: like Yosuke had kept him waiting for a while, and he had better things to do.

"You sure were out for a while," he said. "Sleep well? Sorry the place isn't more comfortable. If you'd let me know you were coming, I'd have neatened up a bit. "

Yosuke looked down at himself blearily. He could feel that his glasses were gone, but even without them, the source of his immobility was immediately evident: Adachi had tied him up with some kind of caution tape. He could feel that his arms had been pulled behind his back and bound at the wrists, and they seemed to be connected to a length of tape that bound his ankles behind him, tight enough that it made him need to arch his back a little. Additional bindings secured his body to something hard behind him. The ties were tight enough to feel uncomfortable, if not quite painful, and the tape was strong enough that it didn't give at all when he tried to pull against it.

"Seriously, though -- a solo attack? I'm almost disappointed. I knew it wouldn't be hard to take you guys down, but even I didn't think any of you would be stupid enough to just give yourself to me as a hostage."

"You won't get away with this," Yosuke said. "The others --"

"Oh, I know they'll come for you," Adachi said. He sounded tired. "And I know that you could probably use that persona of yours to get out of those restraints as soon as I turned my back. It's not worth the energy to try to keep you hostage for real."

Yosuke frowned. That wasn't the answer he had expected at all. 

"... So what?" he said. "Is this just supposed to scare me? Because I'm not."

"Can the bravado. What I'm saying is, I'm not going to keep you forever. But as long as you're here, maybe you can help me with something. I think you're just the right person for the job, actually."

"You think I'm going to _help_ you?"

"I don't think you have a choice." For the first time, Adachi smiled. It was a mean little smirk, and it made him look totally different from the bumbling policeman who had helped with their investigation back in the real world: now, he looked ugly and cruel. Just the sight of that expression made Yosuke's blood heat up.

He was going to say something else, but then Adachi turned around and ducked behind one of the many pillars that scattered the landscape. He emerged seconds later with something in his hands.

It was a potted plant, only a few inches tall, with shiny black leaves the color of an oil slick. 

"There were a whole bunch of these in one of the rooms," he said with tinny cheer. "Now, I'm not an idiot, so I have a general sense of what they do, but I haven't actually tried them yet. You get to help me test my theory."

There was something unsettling about the plant. It may have just been the dim light of the TV world messing with his eyes, but Yosuke could swear that it looked blurry at the edges, haloed by some sort of dark aura. The way its leaves fluttered and rustled as Adachi carried it almost made it look like it was moving on its own, turning its leaves toward Yosuke. He couldn't say why, but he felt suddenly certain that it was as aware of him as he was of it -- that in whatever way a plant does, it was looking at him.

A full-body shiver coursed through Yosuke, completely involuntary. It made him feel hot all over, in a nerve-wracking way that was almost, weirdly, pleasurable. He looked up at Adachi to see if he'd noticed, but Adachi's attention was still on the plant, which he shifted in his hands and then set down on the ground, just in front of Yosuke's knees.

It was a shock to feel Adachi's hands on his belt.

"Relax," Adachi said in a bored tone. "I just need to get this out of the way."

"T--to do what?!"

"You'll see. Just hold still."

"No -- stop --"

But there was nothing Yosuke could do with his limbs restrained. Even as he tried to twist his hips away, he couldn't stop Adachi's long, cold fingers from unbuckling his belt or unzipping his fly.

The air was cold on his bare skin. He shivered, as Adachi shoved the fabric of his jeans down to mid-thigh. 

Adachi reached for Yosuke's briefs next, but his hand stilled halfway. When Yosuke looked down to see why, he realized that somehow, for who knows what reason, he'd gotten half-hard.

"Really, kid?" Adachi said. "This is what does it for you?" He sounded faintly disgusted. Yosuke flushed.

Then Adachi's hands were on his underwear, peeling it away from his skin so that there was nothing to shield him at all. His fingers didn't linger there, working the fabric down his thighs in an efficient, clinical fashion, stopping when the briefs were just above Yosuke's knees.

Yosuke realized he was panting.

But then, to his utter confusion, Adachi let him go. He leaned back. And he shifted to look, not at Yosuke's face or even his embarrassingly erect junk, but at the plant nestled between his legs.

Yosuke followed his gaze. When he did so, he nearly had a heart attack. The plant was much bigger than it had been a minute ago. It was now a coiled vine several inches in length -- and as Yosuke watched, it stretched another few fractions closer to his skin. It was growing before his eyes.

"W--what the hell?"

"Yeah, these things are pretty fast-acting. Impressive, huh?"

"Get that thing away from me," Yosuke said, in a voice that he hoped sounded more commanding than scared. He didn't know why, but the thought of that vine touching his skin gave him the creeps. "What do you want? Do you want information? I--"

"You don't have a great memory, do you? I just told you what I want."

The plant stretched closer. It was now only a hand's length away from his crotch.

"Are you ... are you trying to hurt me? Is this payback, or -- torture, or --"

"I'm trying to conduct an experiment."

"No -- stop, don't, please, wait," Yosuke said, all in a rush. "I -- I'll listen to you." He had to buy himself more time. He tried to reach for his persona in his mind. It was hard to concentrate without his glasses. But just when he thought he might sense it, a rough touch interrupted his thoughts. The plant was nudging the inside of his thighs, right up against his junk.

Adachi smirked. "I don't think I'm the one you should be trying to negotiate with."

Yosuke froze. In perfect clarity, he felt the plant nose its way further back, underneath his balls, but more slowly now, like it wanted to take its time exploring. It crept along his skin until it was right against the edge of his asshole. And when he felt it there, he came back to himself, adrenaline flooding through him in a dizzy jolt, and he tried to wrench himself away with all the strength he had. 

But even then, the tape held him immobile. 

He sucked in a startled breath as he felt a solid pressure against his entrance -- a weird, tight, uncomfortable sensation, nothing like he would have thought it would feel to be touched there -- and at first he thought that was all the plant was doing, was just rubbing him in that spot where he'd never been touched by anyone; but then it felt like there was this surge of motion, this squeeze, almost, and all at once he felt the plant really entering him, going inside.

"Get it out," he gasped.

"Hm?" Adachi frowned. "Get what out?"

"The plant," he said. "It -- It's inside me."

Adachi took a cursory look down below. "Don't be a pussy. It's barely even in there."

"No, it --" Yosuke could feel the plant squirming into him. The tip was cool and slick and tapered, narrow enough that it fit inside him easily, no bigger than a finger, at most; but it felt alien and wrong inside him all the same, stretching him slowly. "It can't -- it hurts."

"It's not even that big. You just need to relax."

The plant pressed deeper, making Yosuke wince. His muscles were tight against it, but not strong enough to keep the vine from working its way another few inches inside. Further down, it felt thicker.

"Please," Yosuke begged. "You have to take it out, it's ..." The way it moved felt so strange -- almost liquid, or like a snake or something, somehow soft and solid all at once. "... It's going in deeper, you need to pull it out, I --" It pulsed. "-- I, ah --"

He shuddered, swallowing the rest of his own words as the base of the plant rubbed against a sensitive spot inside him, a little bit of skin that he hadn't even known was there.

"You what?"

Yosuke gulped. He could feel the plant inside him, the whole foreign length now, wriggling around and stretching him full. Something about how thick it was now, or the way it was moving, maybe, was making him begin to feel strangely hot and sensitive, the way he imagined a cat would feel if you rubbed its fur the wrong way -- not painful exactly, but not good either, just wrong enough to make him feel on edge.

"Please just take it out," Yosuke said. Another few inches. He shifted his hips the smallest fraction, and that somehow just made it worse, pushing the plant deeper still and creating more unbearable friction against those raw spots inside him. He bit back a moan. He was seriously hard now, and he didn't even know why, and the fact that Adachi was watching made the whole thing a hundred times worse. 

"I mean it," he tried again. It was becoming difficult to string words together, but he tried anyway. "It's ... it's too much – it feels weird –" He blinked sharply, as the plant did this sort of -- twisting thing that made his breath come short. "-- I can't make it stop, I --"

"You don't say." Adachi glanced down, taking in Yosuke's stirring cock and the plant working its way into his ass with the same idle curiosity. Yosuke wanted to cover himself up, but the humiliation that coursed through him just made his cock harden. 

"I don't know, though," Adachi said. "It kind of looks like you're enjoying it."

The plant twisted again, sliding right against that tender spot, and with a gasp, Yosuke came all over himself.

There was a moment of dead silence. Even Adachi seemed unsure of how to react. But after a minute, his composure returned, and rolled his eyes. "Teenagers."

When the orgasm died down, Yosuke was left with a cold, sick feeling inside himself. The plant felt even bigger and more uncomfortable inside him than it had before. He could feel Adachi's eyes on him, judging him, his seed-coated stomach and his limp dick.

He waited for Adachi to laugh. He waited for him to bend down and take the plant out. He'd gotten what he came for, right? Humiliation accomplished. Not like it could get any worse than this.

But Adachi didn't move. Contrary to all expectations, he was just standing there, looking down at Yosuke, with an expression that suddenly seemed almost ... thoughtful. 

Yosuke followed his gaze down warily. At first he didn't notice it. Then, with a cold shock, he saw what had caught Adachi's attention.

There was a lump in his stomach. Not too big -- just the size of a chestnut, maybe. A little rise in his belly that hadn't been there five minutes before, right around the spot where he could feel the vine curled up inside him.

Bile rose up in Yosuke's throat.

"This is sick," he said, in a small voice. "You're -- you're seriously sick. What's it going to do now?"

Adachi didn't say anything in response to this. He just gave Yosuke one more look -- a looked that seemed to say _You really are hopeless_ \-- and then moved to sit down, right there, on the ground. Getting comfortable for whatever was coming up next.

The plant began to move again. Yosuke couldn't help but squirm, gasp helplessly as it crawled further inside him. When he looked down again, the bump in his stomach was bigger.

"W--What do you want?" he asked. "I ... I'll do whatever you say, please." His breath hitched again, as the plant made another cruel twist. It felt like every breath he took was sucking it deeper inside of him. 

"Oh? That's not what you said earlier."

"I'm sorry," Yosuke said. His heartbeat sped up as he watched what was going down below -- his belly swelling outward in tiny fractions, so small you'd hardly notice the change unless you were really paying attention, as more and more of the plant coiled inside. He could feel his shirt getting the slightest bit tighter, the bottom edge starting to ride up as the vine stretched him. "I'm sorry, I didn't mean it -- I'll help you." He gulped in a breath, and forced himself to meet Adachi's eyes. "I'll do anything."

Adachi looked unimpressed. " _Anything_ is pretty vague."

"W--whatever you want. Just tell me, and -- and I'll do it." Yosuke shuddered and blinked away tears and made himself keep speaking. "Please, I'm sorry, just don't let it go any deeper, don't let it get any further inside me ...."

"What, it doesn't feel good in there?"

"No," he moaned. He was starting to pant now, hiccupping in these increasingly frantic little breaths, but it felt like he couldn't get enough air. "It's too much -- you ... you have to g--get it out."

Just then, something slick and flexible began to slither its way up his thighs. Fighting his lightheadedness, Yosuke looked down. It was more plant matter: two small vines this time, no thicker than the cord of his headphones. They moved quickly up his body; as he watched, too startled to react, they wrapped their way around his hipbones, and then he could feel them curling up his back.

"What are they doing?" he asked, his voice shaking. "Stop them, please, get them off--!"

At this, Adachi sighed.

"How am I supposed to know what they're doing?" he said. "It's a plant. It can't talk."

"B--but --" The two new vines were up to Yosuke's shoulder blades, now. They tickled his skin, making him shudder. Then they were over his shoulders and crawling up his neck, and he couldn't stop shivering at the feel of them there, even worse than before, like fingers trailing across his skin. 

Now they were on either side of his jaw, and he could just barely see them at the corner of his vision -- and now -- now --

Yosuke whimpered as the twin vines crept into his ears. He could do nothing to stop them as they traced the shells, so sensitive, and then slid in, in, in.

It didn't hurt. It felt like water, rushing in all at once -- but he could feel them inside, rooting their way inside him, soft and damp. 

He could _hear_ them. They sounded wet and sticky. He shuddered and twitched, and it was like that sound was transmitting all through him, resonating across every inch of his skin, making it all ten times more sensitive. Every movement of the vines sent a little jolt of arousal through his body, cutting through the nausea and discomfort and making his cock start to stir with renewed arousal.

There was something hypnotic about the sensation. It felt like the vines were sucking, almost. Like they were siphoning something out of his brain, emptying him, until he was nothing but feverish heat and mounting pressure.

He could hear himself gasping like it was someone else on the other side of a wall. He could feel himself writhing in the plant's grip, twisting as much as his bindings would allow. He could even feel the stalk down below push up further into his belly, practically up to his chest by now, and he knew that if he looked down he would be able to see it stretching him, watch it crawl upward in real time.

But all that sensation was muffled, slow motion, almost. Yosuke moaned, as all the plants burrowed deeper into him: further inside his head, further up his body. He couldn't even remember how to move his muscles now to try to resist their assault. He trembled as he was filled, as his vision fuzzed at the edges, as his cock twitched, so full and thick now, drooling with pre-come -- as he started to feel a tight, itching pressure in his chest, and then at the base of his throat.

Adachi said something then, but Yosuke wasn't even sure what it was. He gasped out something desperate and nonsensical, a plea or a moan or something else -- cried out. 

And then he couldn't say anything at all, because it was in his throat. He coughed, and gagged, and then, all at once --

-

 _Well_ , Adachi thought to himself, _as diversions go, this one could be worse._

He'd honestly expected to be bored, waiting here in the TV world, nothing to entertain him but idle fantasies of what he was going to do to Seta's crew when they arrived. He hadn't actually expected anyone to find him so quickly. That it had been just one of them, and Hanamura no less -- the kid with more mouth than brains on a good day -- had been a stroke of luck. And as for everything that followed ... well, that, he'd just improvised. But he was starting to think he had a talent for thinking on his feet.

Hanamura had undergone a thorough transformation in the past half hour. He'd been so animated when he'd first woken up, so full of righteous outrage that it was enough to give a person a headache, but the plant had sapped that out of him in short order. As it grew, it had made his movements sluggish; it had filled him up, distending his belly until it was swollen and heavy. And in time, it had gone the only place there was left to go, the destination Adachi had been banking on it reaching this whole time: straight out the other end of him.

At first, Adachi had thought he might have to help out with that part of things; it would have just figured if the kid chose now of all times to shut his mouth. He was so scared, he might have tried to keep the plant in there with willpower alone, and maybe Adachi would have needed to give him some hands-on assistance: a little push against his belly, maybe, or a squeeze of the throat, or even just pinching his nose shut so that he would have to open up to breathe. It might have been entertaining, to see him try so hard to hold it in, to watch the panic and fear flood his face the moment when he finally realized he couldn't any longer.

But ultimately he'd been spared the hands-on treatment; the plant had done all his work for him. And that had been interesting, unexpectedly so, seeing the way that Hanamura's expression dulled as it entered his brain; how his breath sped up, his face started to flush, like a chick in a porno right before the money shot. If it had been anyone but a gawky high school kid, it almost would have been hot.

By the end, Hanamura wasn't even trying to stop the plant; by the time it was in his throat, he seemed to want it there.

He'd parted his lips, and his throat had bobbed just once, and he'd let out a soft, wet groan as the plant spilled out onto his tongue. Just a little, just the barest hint of color, but more soon followed, a whole tangle of stalks and leaves, until Hanamura's mouth was filled with them, his lips stretched wide, the residue spilling down his jaw. 

He'd moaned as it filled his mouth, practically suckling at it, maybe in a pathetic attempt to swallow it back inside him. Maybe just because he couldn't get enough of the taste.

Now the plant had totally colonized him. Some bits of it were still digging around in his ears, doing who knows what, but the rest was working his way out his mouth, slowly, making his cheeks bulge and his eyes water. You'd figure it had to be uncomfortable -- the muffled noises Hanamura was making seemed to indicate as much -- but the fear had gone out of his expression a while back; at present there was only a dull, bovine look of confusion, as though he couldn't understand why his mouth was so full, why he couldn't keep the mess inside him from coming up his throat. 

He wasn't going anywhere now, that much was certain. Adachi had even loosened a few of his restraints some minutes back, just to see what would happen, but Hanamura hadn't reacted at all.

Now there was just the question of what to do next.

Adachi shifted where he sat, considering his options. The obvious choice was to leave Hanamura be. He clearly was in no state to escape, and it wouldn't do to be caught here when the rest of his little gang caught up. He ought to fall back and plan for their arrival, maybe even lay some sort of ambush for them. But Adachi knew he had time yet before the others arrived, and the idea of just getting up and leaving, after all the effort he'd spent getting Hanamura into this condition, seemed a little bit of a waste.

So what, then? Stay, until the novelty of watching Hanamura turning into a human vegetable lost its appeal? Up the ante, somehow?

As he thought, he looked Hanamura up and down, searching for inspiration. His eyes ended up catching on the kid's groin. It hadn't received much attention once the plant had gotten up into his stomach, but his dick was still hard anyway, red and moist and straining up against his belly. That vine had to be doing a number on his synapses, for him to still be turned on in this state. Adachi wondered if Hanamura even felt anything there anymore.

It was curiosity that made him end up reaching out, ultimately. Definitely not lust; even if he had been into high schoolers, or men at all for that matter, high school boys being molested by sentient plant life were a bridge too far for his own libido. He just wanted to see what would happen if he messed around a little, was all.

When he did, the reaction was gratifyingly immediate. As soon as his fingers made contact with Hanamura's length, Hanamura let out a muffled whine, and began twitching his hips, rubbing his dick against Adachi's palm in little incremental jerks. 

Adachi pulled his hand back. Another whine, more desperate this time. When he looked up, he saw that the kid's cheeks had flushed, and his eyes were unfocused, and his breath was coming heavier than he remembered it being before.

Slowly, he reached out again. The exact same thing happened: the moment he got close enough to touch, Hanamura started making noise and rutting up against him. This time, instead of pulling away completely, Adachi just lifted his hand back a little, so that Hanamura could reach it if he lifted his hips an inch or two. 

Which was exactly what Hanamura did. With a grunt of effort, he canted his hips up into Adachi's grasp, and rubbed his dick desperately against his palm for a moment, before his muscles gave out and he slipped back onto the plant. After a few more seconds of panting, he repeated the motion. It seemed as though there was a little strength left in him after all; even with the plant impaling him, Hanamura thrust up again, and then again, with a gradually mounting urgency, until he was practically humping Adachi's hand.

Then, abruptly, he seized up, and a pained expression crossed his face. Adachi snatched his arm back right in time, as Hanamura's shoulders heaved, and then he retched; and then, to Adachi's slight surprise, he gagged up a truly massive length of plant matter, several inches at least.

Adachi nearly laughed out loud, when he realized why. Of course -- moving like Hanamura had been just now must have agitated the plant. By working his hips like that, he'd practically been shoving it into himself.

Hanamura whimpered dejectedly, as the last of the plant left him. He was trembling now, his muscles no doubt exhausted from the effort of expelling so much matter in a single go.

But he was still hard.

So of course Adachi had to try the experiment again. Once Hanamura seemed to have his breath back, he reached out to grasp his cock once more; and sure enough, that made Hanamura moan and start twisting his hips just like before, as though he couldn't help himself.

"Does that feel good?" Adachi said. "You realize you're just making things worse for yourself, right?"

He squeezed the tip of Hanamura's erection, then slowly raised his hand. Hanamura let out a muffled, incoherent whine; it could have meant anything, from "Stop" to "Do that again" to "Help me, I can't breathe." But he faithfully started pumping his hips, whimpering as his dick slipped in and out of Adachi's grip. If he knew what he was doing to himself down below, he didn't seem to care.

This time, when he choked up the inevitable mass of vines and leaves, there was even more than the first time. Remarkable, that the plant didn't ever seem to stop growing.

Adachi had to do the whole thing twice more -- two more handjobs that the kid couldn't resist rutting into like a bitch in heat, two more times that he coughed up everything that was inside him -- before Hanamura finally came. This time, it was just a small, watery squirt. His body shook with the force of it, and his eyes rolled back, and for a second Adachi thought he might have even passed out.

When the kid seemed to come back to awareness -- or however aware you could consider him to be, in this state -- Adachi found that he was feeling quite relaxed. Or no -- maybe satisfied was the better term. The kind of contented feeling you get at the end of a good meal.

He glanced down at his watch. Perfect timing, too; he shouldn't hang around here much longer.

He got to his feet, and regarded the now thoroughly ruined Hanamura Yosuke for one final time.

"Well," he said, "I guess I should go get ready. Those guys will probably be here within the hour. Lucky for you.

"Although ... I wonder how much this'll grow in that time?" He chuckled, and patted Hanamura on the stomach. There was no response from Hanamura; only the wet, sloppy sound of him choking around the plant. "Should be something to see. Shame I'll have to miss it.

"Catch you later, kid."


End file.
